Valve-sparing root reimplantation with a Valsalva graft for a trileaflet aortic valve.

Valve-sparing root reimplantation has become an attractive alternative to conventional aortic root replacement in young patients as a means to avoid the anticoagulation required for mechanical roots while improving the durability compared to bioprosthetic valved conduits. In this video tutorial, we present our step-by-step process for performing a valve-sparing root reimplantation with a Valsalva graft for a patient with an aortic root aneurysm and a trileaflet aortic valve.

Outcomes of aortic valve repair with the reimplantation technique and maintenance of commissural orientation.

Background: Debate still persists on whether valve-sparing root reimplantation (VSRR) of a very asymmetric bicuspid aortic valve (BAV) should be completed such that the asymmetry of the native commissural orientation is retained, or if it should be made symmetric (180°-180°). Herein, we present our approach, in which the native asymmetry is preserved, and the valve is reimplanted in a 210°-150° orientation. Methods: A retrospective review was performed of 130 patients with BAV who underwent VSRR between January 1, 2004 and March 1, 2023 at a single institution. Of this total, 37 were reimplanted asymmetrically (210°-150°). The primary outcome was > moderate aortic insufficiency (AI). Secondary outcomes included severe aortic stenosis (AS), reintervention, and survival. Results: The included 37 patients were mostly male [94.6% (35/37)] with mean age of 46.3 years, and with low rates of comorbidities. At least moderate AI was present in 40.5% (15/37) prior to surgery. All BAV in this series were Sievers Type 1 with a mean commissural angle of 128.2°. Leaflet repair was required in 81.1% (30/37), most commonly involving central plication of the conjoined cusp [96.7% (29/30)] and raphe release [73.3% (22/30)]. There was no 30-day mortality or stroke. At 10 years, the cumulative incidences of > moderate AI, severe AS, and reintervention were 7.6% (0-17.2%), 7.1% (0-19.7%), and 5.3% (0.3-22%), respectively. There was no mortality for the entire duration of the study period. Conclusions: This series demonstrates excellent 10-year outcomes of maintaining commissural orientation in asymmetric BAV reimplantation procedures. However, further study with additional patients, longer follow-up, and direct comparison to symmetric reimplantation for similar BAV morphology is required.

Midterm Results of an Algorithmic 3-Pronged Approach to Bicuspid Aortic Valve Repair.

BACKGROUND: This study evaluated midterm outcomes of a 3-pronged algorithm for bicuspid aortic valve (BAV) repair. Valve-sparing root reimplantation (VSRR) was performed for patients with aortic root dilatation. In those without a root aneurysm, external subannular ring (ESAR) was performed for annuli ≥28 mm and subcommissural annuloplasty (SCA) for annuli <28 mm. METHODS: This was a retrospective review of prospectively collected data of 242 patients undergoing primary BAV repair from April 29, 2004, to March 1, 2023, at a single institution. Primary end points were mortality, structural valve degeneration (SVD), which was defined as a composite of more than moderate aortic insufficiency or severe aortic stenosis, and reintervention. RESULTS: The algorithm was used to treat 201 patients; of these, 130 underwent VSRR, 35 had ESAR, and 36 underwent SCA. Most were men with mean age of 43.8 years (SD, 12.0 years), which was similar between groups. Preoperative aortic insufficiency more than moderate was more common for ESAR compared with VSRR and SCA (74.3% vs 37.7% vs 44.4%, P < .001). At 30 days, mortality was 0.8% (n = 1) for VSRR and 0% for ESAR and SCA. At 6 years, overall Kaplan-Meier survival was 98.9% (95% CI, 97.3%-100%), with no differences between groups (P = .5). The cumulative incidence of SVD was 4.7% (95% CI, 0.1%-9.2%) for VSRR, 6.4% (95% CI, 0%-14.6%) for ESAR, and 0% for SCA (P = .4). Similarly, the cumulative incidence of reintervention with all-cause mortality as a competing risk was 2.2% (95% CI, 0.4%-6.9%), 6.1% (95% CI, 1%-17.9%), and 0% for VSRR, ESAR, and SCA, respectively (P = .506). CONCLUSIONS: A 3-pronged algorithmic approach to BAV repair results in excellent survival and freedom from reoperation at 6 years.

Valve-sparing root reimplantation in patients with left ventricular dilation.

OBJECTIVES: The purpose of this study was to evaluate the association between left ventricular (LV) dilation and outcomes following valve-sparing root reimplantation. METHODS: Patients with an indexed LV internal diameter during systole of ≥2.0 cm/m2 were categorized as having LV dilation. Outcomes were postoperative aortic insufficiency (AI), reintervention and all-cause mortality. The cumulative incidence of each outcome was computed using the Kaplan-Meier estimator. Adjusted comparisons between strata were performed for each outcome using a Cox proportional-hazards model. Where possible, the competing risk of death was accounted for. Multilevel mixed-effects ordered logistic regression was performed for AI grade at follow-up. RESULTS: There were 295 patients of whom 52 had LV dilation. Operative outcomes were excellent; there were no significant differences between groups. Patients with LV dilation demonstrated significant improvement in indexed LV internal diameter during systole overtime. There was no association between LV dilation and postoperative AI grade >2 [hazard ratio 0.88, 95% confidence interval (CI) 0.21-3.67, P = 0.89] or odds of increased AI grade overtime (odds ratio = 0.76, 95% CI 0.30-1.93, P = 0.57). There were no re-interventions among those with LV dilation. Adjusted mortality was significantly higher among those with LV dilation (hazard ratio 5.56, 95% CI 1.56-19.9); however, deaths were unrelated to aortic valve dilation. CONCLUSIONS: LV dilation is not associated with poorer operative outcomes, postoperative AI or reintervention. It is associated with an increased risk of mortality, though not from valvular dysfunction. LV dilation should not deter valve-sparing root reimplantation when otherwise indicated.

In-Human Implantation of a Novel Biologic Valved Conduit for Aortic Root Replacement.

Aortic root replacement is a complex procedure. Recently, the KONECT RESILIA aortic valved conduit (Edwards Lifesciences, Irvine, CA), the first prefabricated biologic valved conduit available in the United States, was approved for use. Here, we report a series of 3 patients representing implantation of the novel Konect AVC. The conduit was implanted in both supraannular and intraannular positions, and the unique design of the sewing ring offers several advantages. The Konect AVC streamlines the process of root replacement and may represent an improvement in terms of ease of implantation and durability.

An All-Optical Excitonic Switch Operated in the Liquid and Solid Phases.

The excitonic circuitry found in photosynthetic organisms suggests an alternative to electronic circuits, but the assembly of optically active molecules to fabricate even simple excitonic devices has been hampered by the limited availability of suitable molecular scale assembly technologies. Here we have designed and operated a hybrid all-optical excitonic switch comprised of donor/acceptor chromophores and photochromic nucleotide modulators assembled with nanometer scale precision using DNA nanotechnology. The all-optical excitonic switch was operated successfully in both liquid and solid phases, exhibiting high ON/OFF switching contrast with no apparent cyclic fatigue through nearly 200 cycles. These findings, combined with the switch's small footprint and volume, estimated low energy requirement, and potential ability to switch at speeds in the 10s of picoseconds, establish a prospective pathway forward for all-optical excitonic circuits.

Large Davydov Splitting and Strong Fluorescence Suppression: An Investigation of Exciton Delocalization in DNA-Templated Holliday Junction Dye Aggregates.

Exciton delocalization in dye aggregate systems is a phenomenon that is revealed by spectral features, such as Davydov splitting, J- and H-aggregate behavior, and fluorescence suppression. Using DNA as an architectural template to assemble dye aggregates enables specific control of the aggregate size and dye type, proximal and precise positioning of the dyes within the aggregates, and a method for constructing large, modular two- and three-dimensional arrays. Here, we report on dye aggregates, organized via an immobile Holliday junction DNA template, that exhibit large Davydov splitting of the absorbance spectrum (125 nm, 397.5 meV), J- and H-aggregate behavior, and near-complete suppression of the fluorescence emission (∼97.6% suppression). Because of the unique optical properties of the aggregates, we have demonstrated that our dye aggregate system is a viable candidate as a sensitive absorbance and fluorescence optical reporter. DNA-templated aggregates exhibiting exciton delocalization may find application in optical detection and imaging, light-harvesting, photovoltaics, optical information processing, and quantum computing.

Coherent Exciton Delocalization in a Two-State DNA-Templated Dye Aggregate System.

Coherent exciton delocalization in dye aggregate systems gives rise to a variety of intriguing optical phenomena, including J- and H-aggregate behavior and Davydov splitting. Systems that exhibit coherent exciton delocalization at room temperature are of interest for the development of artificial light-harvesting devices, colorimetric detection schemes, and quantum computers. Here, we report on a simple dye system templated by DNA that exhibits tunable optical properties. At low salt and DNA concentrations, a DNA duplex with two internally functionalized Cy5 dyes (i.e., dimer) persists and displays predominantly J-aggregate behavior. Increasing the salt and/or DNA concentrations was found to promote coupling between two of the DNA duplexes via branch migration, thus forming a four-armed junction (i.e., tetramer) with H-aggregate behavior. This H-tetramer aggregate exhibits a surprisingly large Davydov splitting in its absorbance spectrum that produces a visible color change of the solution from cyan to violet and gives clear evidence of coherent exciton delocalization.

Excitonic AND Logic Gates on DNA Brick Nanobreadboards.

A promising application of DNA self-assembly is the fabrication of chromophore-based excitonic devices. DNA brick assembly is a compelling method for creating programmable nanobreadboards on which chromophores may be rapidly and easily repositioned to prototype new excitonic devices, optimize device operation, and induce reversible switching. Using DNA nanobreadboards, we have demonstrated each of these functions through the construction and operation of two different excitonic AND logic gates. The modularity and high chromophore density achievable via this brick-based approach provide a viable path toward developing information processing and storage systems.